What is table scan , table seek and Index scan , index seek

• anoop.mig29

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  February 1, 2013 at 5:35 am

  #269744

  Hi my question is very simple but i am very confused , i have searched on net but still not able to grasp knowledge.i want to know is table scan,table seek ,index scan and index seek.IF an eg is provided then better .

  i mean to say suppose there is table 4*4 table(4 rows and 4 columns) then how table scan works and how table seek works . similarly for Index

• Gail Shaw

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  February 1, 2013 at 5:45 am

  #1583390

  Table scan - read of the entire table

  Table seek - no such thing

  Index scan - read of the entire index

  Index seek - search into an index for a specific value or set of values.

  Gail Shaw
  Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
  SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

  We walk in the dark places no others will enter
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• anoop.mig29

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  February 2, 2013 at 7:41 am

  #1583656

  GilaMonster (2/1/2013)

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  Table scan - read of the entire table

  Table seek - no such thing

  Index scan - read of the entire index

  Index seek - search into an index for a specific value or set of values.

  Thanks Gila for reply . but by entire Table means means reading each and every columns for every row in an table. Am i correctly interpreating

• Gail Shaw

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  February 2, 2013 at 8:05 am

  #1583658

  Well, reading all of the data pages for the table.

  Gail Shaw
  Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
  SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

  We walk in the dark places no others will enter
  We stand on the bridge and no one may pass